<p>
          Checks that long constants are defined with an upper ell. That
          is <code>' L'</code> and not <code>'l'</code>. This is in accordance with the Java
          Language Specification, <a class="externalLink" href="http://docs.oracle.com/javase/specs/jls/se8/html/jls-3.html#jls-3.10.1">
          Section 3.10.1</a>.
        </p>


<p>
          The capital L looks a lot like <code>1</code>.
        </p>